The world's tiniest battery could power a new generation of wearable sensors
Energy storage might have been revolutionized thanks to a common dessert dish.
Scientists at the Chemnitz University of Technology developed the world's smallest battery, a Swiss-roll-inspired self-assembling device that could be used to power small sensors in the human body, according to a new paper published in the journal Advanced Energy Materials.
The breakthrough in energy storage technology was created via the so-called Swiss-Roll process, inspired by the famous layered, spongey dessert. In this case, the researchers layered current collectors and electrode strips made of polymeric, metallic, and dielectric materials onto a tensioned water surface.
By peeling off these individual layers they could release the tension on the water surface, allowing the materials to snap back and roll around each other. The scientists described the resulting device as a "self-wound cylinder micro-battery".
A battery as small as a grain of dust
The micro-battery is roughly the size of a grain of dust — one square millimeter across — and it has a minimum energy density of 100 microwatt hours per square centimeter. According to study lead Professor Oliver Schmidt, that density will improve over time: "There is still a huge optimization potential for this technology, and we can expect much stronger micro-batteries in the future," Schmidt explained.
While obviously limited by its size, the team behind the new device says it could eventually be used in tiny chips for biosensors in the human body. They claim the micro-battery could power the world's smallest computer chips for roughly 10 hours, which would allow a whole host of new applications in biosensors — devices that typically rely on harvesting energy via alternative means to overcome their size limitation.
On the other end of the spectrum, MIT researchers recently figured out how to develop batteries that are one-kilometer long, and they said "there's no obvious upper limit to the length" they could reach. In order to help the world shift away from fossil fuel consumption, scientists will have to develop all sorts of energy storage solutions to power the devices of the future.